摘要
用偏光显微镜（ＰＬＭ）和透射电镜（ＴＥＭ）观察了 ６７Ｐｈ（Ｍｇ１／３Ｎｂ２／３）Ｏ３－３３ＰｂＴｉＯ３单 晶的畴结构，在ＰＬＭ下，光学质量不同的晶体具有不同的畴结构，透明晶体具有毫米尺度的大畴，透明性 差的晶体的带状孪生畴宽约为 ０．１ｍｍ；在 ＴＥＭ下，雾状晶体中存在着复杂的微米尺度的孪生畴，而均匀 晶体中存在着不规则的微米尺度的 １８０畴．原位 ＥＤＳ分析表明，在孪生晶体中存在 Ｎｂ－Ｔｉ－Ｍｇ－Ｐｂ－Ｏ 非晶相．透明晶体的介电和压电常数显著地高于雾状晶体．讨论了化学不均性对畴结构的影响．
Ferroelectric domains in 67Ph(Mgl/3Nb2/3)O3--33PbTiO3 single crystals were studied by means of polarized light microscope (PLM) and transmission electron microscopy (TEM) PLM photographs revealed that the domain structures vary with crystal quality. The transparent crystals are usually characterized by large domains millimeters in size. Banded twin domains were found in translucent crystals. TEM study gave similar domain structure to those observed by PLM. The complicated twins were observed in translucent crystals. The irregular 180' domains with size of micrometers were observed in transparent crystals. The in situ EDS analysis showed that the crystals with twins contain Nb-Ti-Mg-Ph--O non--crystalline phase. Dielectric and pizoelectric constants of transparent crystals are better than translucent crystals. Electrical properties and the relevance of domains to corresponding microstructures were briefly discussed.
出处
《材料研究学报》
EI
CAS
CSCD
北大核心
2000年第5期457-462,共6页
Chinese Journal of Materials Research
基金
国家自然科学基金重大项目!59995520
上海市基金资助项目!97EZ14036
上海市科委博士后基金资助项目.
关键词
铁电畴
铁电相变
畴结构
67PMN-33PT铁电单晶
Pb(Mg1/3Nb2/3)O3-based ferroelectric crystal, ferroelectric domain, ferroelectric transition
